Doing God's work - it's not a phrase that you often hear in connection with TV shows.

Jim Mora's Mucking In is one show that fits the bill, with it's local unsung heroes getting a garden makeover. The people are true salts of the Earth, giving up their time to work with disabled kids or care for the elderly.

Missing Pieces is another, the one that tracks down estranged family members. These shows make you feel good because they do good.

It's a little different when the focus of the show is people who maybe sold some P or bashed some joker across the face with an iron bar.

Having said that it seems to me that the remarkable Songs from the Inside (Maori TV, Sunday, 8pm) is one of those rare TV shows that's actually doing some good.

Four very accomplished Maori musicians - Anika Moa, Maisey Rika, Warren Maxwell and Rua Aperahama - go into two Wellington prisons, Rimutaka (for men) and Arohata (women), and work with inmates who want to become songwriters.

It's the sort of show that would probably have the Sensible Sentencing Trust staff screaming at the TV before reaching for the remote but not quite getting to it before they projectile vomit all over the lazyboy, before cleaning up with extra thick paper towels and calling talkback while still trembling with rage.

"Prison, blah blah, five-star hotel, blah, blah, with colour TV and now personal tutelage from professional songwriters!"

But life inside is clearly not of the five-star star hotel variety, and no one here is having a holiday.

In episode one we met the mentors. Rua Aperahama is the alpha male here, (the Simon Cowell) best known of course for the 90s smash hit What's the Time Mr Wolf.

Warren Maxwell (Trinity Roots) is made of softer stuff and acknowledges his own "good upbringing" as he finds himself wondering why so many of the inmates didn't have such good childhoods.

By episode two we learn that Anika Moa has more experience with the prison system than the others, her brother has been inside and her dad spent many years behind bars.

She's the joker in the pack, the fly that brilliantly upsets the sometimes worthy ointment. Kind of like Paula Abdul, although less mental (The X Factor/Idol comparisons come to mind partly because the producers have gone for the reality TV technique of having the prisoners and the musicians constantly telling us how they feel about every step of the process).

Less familiar is the fourth musician Maisey Rika. Like Aperahama she's a great singer and more Maori than mainstream. Given that 55 per cent of the prison population is also Maori, that makes nothing but sense. In a way it's that statistical millstone that really anchors the series.

By episode two we're starting to get to know the prisoners who are being mentored, and there are some wonderful characters already emerging, but we don't yet know the answer to the obvious question, the elephant in the room. What are they're in for?

That information will no doubt be revealed as the series progresses as we get to know the inmates. It's one of the things that will keep me watching, as will the hints of real talent that are already shining through the brief snippets of performances.

I came in on the second episode but I felt like I'd missed something and went back to the first episode via the Maori TV site. It's worth doing if you missed it. The induction process and the background is all there, and it's illuminating.

The fear of God is drilled into the musicians by prison staff. Warnings are given about not giving too much information or doing favours for the inmates. A story about someone who made a phone call on behalf of an inmate was chilling, the call turned out to be, not to a loved one, but to the victim of a grisly crime.

The musicians are taken aback and start to shit themselves. But the best advice comes from theatre director and social worker, (and former Close to Home star) Jim Moriaty who's worked with many inmates in the past; "Just don't promise anything you can't deliver".

If you were describing it to a teenager you'd could say that is was The X Factor crossed with America's Toughest Prisons. It has elements of both, but I also reckon it's also a little bit Mucking In, it's just that the makeover happening here isn't of the garden variety.